<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        let x = /[0-9]/g
        //let x = /[^0-9]/g取反
        let y =' 2,3,4'
        let z = y.match(x)
        console.log(z)
    </script>
</body>
</html>